The present invention relates to switches and control devices such as joy sticks, on/off switches and variable control switches. The invention further relates to control panels incorporating multiple switching devices. The invention further relates to switches, joysticks and the like wherein the user actuated movement of the device is detected by a pressure sensor, without the use of electrical contacts within the switching or control device and the corresponding information is relayed electronically to a central processing unit.
The field of user actuated control means includes switches, joysticks and the like. Examples include 2-position on-off switches, multi position variable control switches (such as light dimmers), push button switches, multi position joysticks, and others. Such devices are characterized by a moveable member, which typically comprises a lever arm or push button actuated by a user, and a detector for detecting movement of the member. Within conventional on/off switches, a lever arm or toggle is associated with electrical contacts, wherein within a first position electrical contact is made, and when actuated by a user to a second position, electrical contact is broken. In an alternative arrangement, such as is found in joysticks and other like multi-position control means, a lever arm or the like is associated with a sensor for detecting the particular position of the arm. The arm may be mounted for sliding contact along a linear path (e.g. a light dimmer) or for movement on a 2 dimensional plane (e.g. a joystick). Conventionally such arrangements are similarly exemplified by various electrical contacts.
There is a need for switching and control units that incorporate a minimum of moving parts, are relatively inexpensive to fabricate and which do not rely on electrical contact in order to achieve a switching function. This results in less expensive and more reliable arrangement. In particular, such a need is experienced within the automotive industry, which uses a relatively large number of user-actuated switches and control means.
For example, within an automobile, switches and controls are generally found within the seat, door, steering wheel and front panel, for controlling a multitude of function and vehicle operations. Typically, pushing a switch sends an electrical detection signal via a supply wire to an actuator unit, possibly within a micro controller to perform the initiated function (see U.S. Pat. No. 4,809,180). These automotive switches are used to activate or deactivate circuits to perform certain functions (see U.S. Pat. No. 4,888,535).
The switches discussed above can be used in a variety of locations within a vehicle. Manipulator switches may be found on the side arm of a seat for altering its position and height. These switches are used to adjust certain features of the automobile according to the occupant""s preferences. Similar switch panels may be found on the door armrest to activate power window and power mirror functions. Similar switch arrays may be found on the driver control console for activating many of the primary driving facilities in the car. A detection switch may also be used to detect current status of an automobile component, such as the open/closed status of a vehicle door. Related to this detection switch is the courtesy switch used to turn on a vehicle light when the car door is opened or trunk lid lifted or glove compartment opened. These switches include an actuating plunger which moves under spring pressure when spacings between a moveable and fixed lever increase. This type of lever or plunger is quite common in many switches (see U.S. Pat. No. 4,698,466).
Many occupant control switches are typically membrane switches. Membrane switches usually consists of a pair of parallel contact plates, possibly flexible electrodes, separated in the inoperative position due to the presence of a resilient element positioned between the two layers This resilient element could be a dielectric layer with a specific pattern defining opposing electrodes or an elastically yielding body filled between the plates. When a switch is touched or contacted, the two metal plates or electrodes make electrical contact, activating the proper response. Many membrane switches include an operating press member, acting on one metal plate, displacing the member into operative position (see U.S. Pat. Nos. 5,588,673, 5,743,386, 5,756,950 and 5,198,629).
Occupant controls such as a steering wheel, brake pedal and accelerator pedal may be fitted with simple switches to detect activation or with position sensing devices to detect the degree of actuation. Many brake pedals are comprised of a support bracket mounted to the firewall, brake pedal lever hinged thereto, resilient element urging brake pedal rearwardly and a switch located on either the support or lever. When these two members contact, due to the forward movement of the lever, the switch is activated, which connects the lever member to the brake system push rod (see U.S. Pat. No. 4,297,550). A number of such occupant control technologies have been cited in patent literature.
In addition to installing switches to ensure occupant comfort and pleasure, automobiles also include a suspension control apparatus that is used to provide a comfortable and stable ride. This apparatus counters change in the attitude of a vehicle, which may occur during braking, accelerating, turning and so on.
A suspension control apparatus generally consist of a fluid spring chamber, which is located between each road wheel and body of the vehicle, in addition to multitude of sensors. Sensors commonly implemented include vehicle height, speed, steering angle and acceleration sensors. Based on signals from these various sensors, the suspension control device regulates the amount of hydraulic fluid to be supplied to or discharged from the suspension systems (see U.S. Pat. Nos. 5,217,247; 4,887,840; 5,701,245; and 5,330,025).
User-actuated controls may be placed into two general categories. Within a first, a switch describes an on/off motion. Within a second, a range of positions is detected. For example, a conventional light dimmer or joystick would fall into the second category.
It is desirable within all such applications to provide a simple, accurate and reliable means for detection of position of a control arm.
It is proposed to provide a switch or control means that relies on a pressure sensor of the type described within PCT publication no. WO 99/04234. This type of pressure senor relies on a deformable integrating cavity for detecting a pressure applied to the cavity. Typically, the arrangement is comprised of a material such as translucent foam, which receives wave energy such as light from a source. A detector detects intensity of the light or other energy within the material. The sensor operates on the principle whereby the deformation of the material increases the light intensity in the region around the source. Thus, in the case where the source and detector are adjacent to each other or in the vicinity of each other, an increase in pressure on the material and consequent deformation in the region of the light source results in a consequent increase in the intensity of light detected by the detector. The resulting signal may be transmitted to a processing unit, which in turn quantifies the pressure experienced by the material. In one version, the light source and detector each comprise single or multiple fiber optic strands leading to and from the sensor. Within this arrangement, multiple sensors and detectors may be poisoned at different positions around the sensor mass, thereby detecting the location of pressure applied to the material. For example, a sheet of deformable material may be underlain with a planar array of light emitter/detector pairs, which detect and localize deformation of a particular portion of the sheet.
This principle is particularly advantageous for use with switches and the like, since the position of a user-moveable arm may be detected by a pressure sensor of the type described above.
The invention comprises in one aspect, a user-activated switching or control means, comprising a moveable arm having first and second ends, the first end being moveable by a user; a mount for moveable mounting of the arm; a deformable or compressible material in contact with the second end of the arm, the deformable material comprising an integrated cavity for scattering or defusing wave energy such as light; a wave energy source and detector in communication with the deformable material; and processing means to receive signals from the detector and convert the signals into useable information relating to the position of the arm relative to the deformable material.
The arm and the integrating cavity are arranged such that movement of the arm in a selected direction locally compresses the deformable material, thereby transmitting corresponding information respecting the arm position to the processing unit.
Conveniently, the deformable material may comprise a deformable, light translucent material such as foam, and the wave energy source and receiver respectively comprise fiber optic cables, associated with a light source and detector, respectively.
In a further aspect, multiple light sources and receivers are provided at different positions around the deformable material, thereby detecting multiple positions of the arm.
In a further aspect, the invention comprises a lever arm switch, wherein the arm is pivotally mounted to a pivot, and the second end of the arm comprises a base region in engagement with an elongate integrating cavity such as a foam block. In this arrangement, movement of the arm in one direction or the other about the pivot achieves a corresponding movement of the base, which compresses a corresponding. Conveniently, a light source and detector pair are positioned at the respective ends of the deformable material, thereby detecting movement of the switch in either direction.
In a further aspect, the invention comprises a toggle, wherein the arm comprises an elongate member, pivotally mounted at or about the middle thereof. A first elongate side of the arm is in contact with the deformable material, and an opposed elongate side comprises the user depressable surface of the switch. In this version, depression of one side or the other of the arm deforms a corresponding side of the deformable material. In turn, a light emitter/detector pair is associated with each corresponding side of the deformable material. In a further aspect, the elongate arm is pivotally mounted at one end thereof, and the deformable material engages a first elongate side of the arm, the opposed second elongate side comprises the user contact region. In this version, depression of the arm at any position thereon deforms the deformable material, thereby providing a signal to the detector. In this version, only a single light emitter/detector pair is required.
In a further aspect, the invention comprises a rotary switch, having a pivotally mounted rotatable member. The rotatable member has paired opposing contact surfaces, which may be conveniently be provided by means of an arm extending a outwardly from the rotatable member having opposed surfaces. One or more pads of the deformable material are in contact with the respective surfaces, whereby rotation of the rotatable member in a selected direction deforms a corresponding. Deformation of the deformable material is detected by a corresponding array of light emitter/detector pairs. Conveniently, the deformable material comprises two opposed pads on either side of the arm, whereby rotation of the knob in a first direction compresses a first of the pads, and rotation in the second direction compresses the second of the pads.
In a further aspect, the invention comprises a lever arm position detector, such as a joystick or a slider type switch, wherein there is further provided a mechanical motion constraint to limit movement of the arm during or following actuation by the user. In one version, the arm is arranged for linear slidable movement, and may be mounted within a housing. The arm comprises in this version a user grippable member, having an extension therefrom for contacting a pressure-sensitive pad. A deformable pad is mounted for contact with the extension, whereby movement of the arm relative to the pad deforms a portion of the pad at the contact point. The pad is underlain by an array of light emitter/detector pairs, whereby the position of the arm relative to the pad is detected by a relative increase in light intensity within the pad, where the arm contacts the pad. The arm may be arranged for unidirectional or multidirectional movement relative to the pad. Conveniently, a frictional contact member contacts the arm for restricting movement of the arm relative to the housing. The arm may comprise a base portion, a part of which is slidably retained within the housing for frictional engagement with the housing. A user grippable portion may extend upwardly from the base. In a related aspect the arm may be mounted for rotary movement within the housing, with a broadened base region. A protrusion extends from the base from a position displaced from the user grippable portion, whereby rotation of the user grippable portion rotatably displaces the protrusion relative to the pad and depresses a corresponding region of the pad, thereby signaling the relative radial position of the arm.
In a further related aspect, the invention comprises a joystick wherein the pad is arcuate or semispherical, and in contact with a portion of the arm. The arm in turn is pivotally mounted, and includes a user grippable portion on one side of the pivot mount and a contact region on the opposed side thereof. An array of light emitter/detector pairs is associated with the deformable pad, whereby rotational movement of the arm is translated through the pivot to a corresponding movement of the opposed ends. The emitter/detector pairs are arranged to detect the position of the arm as the same bears on a region of the pad. Mechanical motion constraint of the arm is provided by frictional engagement of the arm against the pad, thereby providing an appropriate user xe2x80x9cfeelxe2x80x9d to the arm.
In a further aspect, the invention comprises a push button switch, wherein the arm is mounted for linear movement relative to the deformable pad. The arm contacts the pad at a single position on the pad, whereby linear movement of the arm deforms the single pad position. A single source/detector pair detects deformation of the pad at the point of contact with the arm.
In a further aspect, the invention comprises a pushbutton type switch characterized by a flexible enclosure, of plastic or other flexible material, which encloses a deformable pad. An upper surface of the enclosure may be depressed by the user, to deform the pad contained within the enclosure. Conveniently, the upper surface bulges outwardly, and features snap action for retaining at least temporarily the depressed configuration. A light emitter/detector pair is associated with the enclosed foam pad.
In an alternate arrangement, a push button switch comprises a plunger housed within a housing, which conveniently includes a portion contacting the plunger to impose a frictional or other mechanical restraint against movement by the plunger. A deformable foam pad and associated emitter/detector pair is housed within the base of the housing, in contact with the base of the plunger, whereby depression of the plunger depressed the pad.
In a further aspect a multifunction switch panel is provided, comprising a deformable pad, associated with multi switch means of any combination of the switch means described above. Multiple light emitter/detector pairs are associated with the pad in the region of the various switch means. A single housing conveniently retains the pad and the switch means.
In a further aspect the invention comprises, an automotive or vehicle pedal, such as a brake pedal, lined on the user contact surface with a deformable pad associated with one or more emitter/detector pairs, whereby compression of the pad by pressure of the user""s feet against the pedal, compresses the pad and transmits a corresponding proportional signal to the control unit. Alternatively, the deformable pad may be positioned elsewhere, in contact with the pedal arrangement, whereby depression of the pedal, deforms and compresses the pad.
In a further aspect, the invention comprises a closure sensor for an automotive or vehicle window, comprising a deformable pad mounted within a window frame in a position for contacting a portion of the window, when the window is in the fully closed position, whereby closure of the window deforms the pad and transmits a corresponding signal to the central processing unit. In a further aspect, the invention comprises a method for detecting window closure, comprising the steps of providing a deformable pad as characterized above, mounted within the window frame of a vehicle and associated with a light emitter/detector pair and a processor unit; closing the window sufficiently to contact and compress the pad; transmitting a corresponding signal to the processor unit; stopping a window closure motor in response to a signal from the processor unit.
These and other aspects of the invention will now be described by way of a detailed description of the preferred embodiments and by reference to the accompanying drawings.